Winhttp.dll library is associated with Microsoft’s Windows HTTP Services. This file is used by several network and Web-based applications.

You may encounter the following winhttp.dll error when you try to install or run MSN messenger:

This application has failed to start because an important component winhttp.dll is not found. Reinstalling the application may fix the error.

Although the error message prompts you to reinstall MSN messenger, it may persist even after reinstallation. This happens because the winhttp.dll file is not a part of MSN messenger, thus reinstalling it fails to fix the missing winhttp.dll error.

Winhttp.dll is actually a standard Windows XP file and to fix the missing DLL issue, you need to download the file from a free DLL Download website. It is important that you save the downloaded file in the \Windows\System32 folder. Saving the file in any other location will not fix the error. After you have saved the file in its correct location, you will need to register it. To do this, perform the following steps:

Go to Start and select Run command

In the Open box, type regsvr32 winhttp.dll and press OK.

In case the DLL file is present on your system but you are still encountering the winhttp.dll error, then a plausible reason for this could be a corrupt winhttp.dll file. There are many reasons due to which a DLL file may become corrupt, the most prominent being a malware infection. Scan of your entire system using a reliable antivirus tool, such as STOPzilla Antivirus and an antispyware tool, such as Spyware Cease to determine if this is the case. If the scan results show that winhttp.dll is infected, use these protective tools to repair the file. If the file is beyond repair, delete it and download a new copy of the file from the Internet. To prevent any future malware infections, ensure you use Firewall protection and update your protective tools regularly with the latest virus definitions and security updates.

Winhttp.dll errors may also occur if the entries related to this file in registry are tampered with. Schedule regular registry scans, using an efficient registry cleaning utility, such as RegServe to ensure only accurate entries reside in registry.

Winhtttp.dll errors may also occur if your Windows files are outdated. To fix this issue, use the Windows Update option in the Start menu to open the Windows Update website. Allow the Windows update website to scan the PC for outdated files, and then proceed to download and install the required updates on the system.

Finally, if winhttp.dll errors start occurring soon after you make some major changes to your Windows configuration, perform a System Restore to rollback these changes and fix the error.